A multifunction printing system (to be referred to as an MFP system hereinafter) realizes a plurality of functions by connecting various functional units such as a scanner unit, printer unit, image processing unit, paper feed unit, facsimile unit, and finisher unit via a system bus or the like.
Unfortunately, many conventional MFP systems become entirely unusable if any of these functional units fail.
In some conventional MFP systems, a faulty functional unit is disconnected to allow other functional units to be usable. Alternatively, if an error occurs while a printing system is operating, another MFP system connected to the network is searched for, and image data is transferred to the found MFP system to cause the system to perform print job redirecting printing.
This MFP system, however, merely causes another MFP system to perform print job redirecting printing as a temporary countermeasure against a failure, and cannot permanently use functional units of another MFP system regardless of whether there is a failure. In addition, the degree of freedom of combination of functional units is low, and realizable functions are limited in many respects.
Also, it is difficult to inexpensively expand only necessary ones of a plurality of functional units in accordance with the needs. That is, functional units are difficult to flexibly combine.
Furthermore, when the MFP system is to be discarded, the whole system must be discarded at once even if the system still contains a usable functional unit whose life has not expired yet. This makes the system inferior in terms of environmental protection and resource protection.